DISEASE IN HAND-REARED GROUSE 435 



have caused the death of captive birds in Maine'" while the scaly-leg mite fCnemidocoptes 

 mutans) which burrows under the scales of the legs, may cause severe inflammation and 

 lameness. Both species are ordinarily poultry parasites. The latter also occurs in pheas- 

 ants and was recently reported from ruffed grouse in British Columbia". 



Among the insect parasites occurring occasionally on grouse are bird fleas (Ceratophyllus 

 diffinis)^" and bird lice (Gallilipeurus cameratus", Lagopoecus perplexus^, Goniocotes sp/"' 

 and Menopon sp.). 



Although the above list may seem long and formidable, in actuality grouse probably do 

 not harbor more parasites than do most other game birds. As has been pointed out, in 

 most cases, large numbers of any given species do not appear in individual birds. It is sel- 

 dom that one bird harbors more than a half dozen difi^erent parasitic forms. It is also im- 

 portant to recall how few of the organisms mentioned during preceding sections have been 

 demonstrated to have disease producing proclivities. The fear that the numbers of grouse 

 in the coverts are seriously affected by their internal and external inhabitants has not yet been 

 substantiated. 



DISEASE IN HAND-REARED GROUSE 



Early experience in the hand-rearing of grouse dcnioiistrated that discouraging losses re- 

 sulted from disease". The maladies observed most comnKinly were blackhead (enterohepa- 

 titis), stomach worm infection, ulcerative enteritis ("quail disease") and coccidiosis. 



The presence of these afflictions was probably due partly to the fact that the birds were 

 raised on the ground or in some form of lifter rather than on wire, partiv that they were 

 usually in contact with ])oultry, directly or indirectly. In some cases, indirect connection with 

 other game birds, particularly quail, may have been responsible. 



Knowledge concerning the means of transmission and spread of parasites and disease has 

 grown. Practical methods of prevention and control based on this knowledge, have been 

 adopted. The use of hens as foster mothers for young grouse has been abandoned. 

 Rearing of birds on the ground is now considered to be not only unnecessary but 

 dangerous. These steps have led from a disheartening period of pioneering to the present 

 phase in artificial propagation when infectious disease is less of a problem than certain 

 aspects of incubation, brooding and nutrition. 



An understanding of the methods used in hand-rearing grouse at the Research Center as 

 described in Chapter XI, Artificial Propagation of Grouse, should logicallv precede the con- 

 sideration of the disease conditions encountered in captive grouse. Described in a nutshell — 

 the eggs are artificially incubated and the newly hatched chicks are transferred to battery 

 brooders with wire floors. At the end of ten days they are placed on wire in a colony house 

 where they remain until they are 6 weeks old, at which time they are transferred to outdoor 

 pens again equipped with wire floors. The nearest poultry are one-half mile away and the 

 only other birds kept at the Research Center are waterfowl and pheasants. 



The sanitary precautions which are an inherent part of the propagation program elimi- 

 nate worm parasitism entirely and reduce even highly contagious diseases, such as ulcera- 

 tive enteritis and blackhead, to a few cases a year, while tuberculosis, aspergillosis and coc- 

 cidiosis are so rare as to hardly require consideration. The use of wire-bottomed pens to 

 prevent contamination of food and water with droppings is the procedure to which this con- 

 trol is largely attributable. 



